/******************************************************************************

    Copyright (C) 2006 Alessio Stalla (alessiostalla@gmail.com)

    This file is part of PrettyProlog.

    PrettyProlog is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    PrettyProlog is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with PrettyProlog; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    See the file COPYING for further details.

 *****************************************************************************/

package prettyprolog.engine.listeners;


/**
 * @author Alessio Stalla
 * A listener that receives events from an Engine. */
public interface EngineListener {
    
    /** Called by the Engine when it finds a solution for its current Goal. */
    public void solutionFound(EngineEvent e);
    
    /** Called by the Engine when the solving process is started. */
    public void solvingStarted();
    
    /** Called by the Engine when the solving process is continued after a pause. */
    public void solvingContinued();
    
    /** Called by the Engine when the solving process is paused. */
    public void solvingPaused();
    
    /** Called by the Engine when the solving process is aborted. */
    public void solvingAborted();
    
}
